<html>
  <body>
    <button onClick="toggle()">Click to Flip</button>
    <div class="item-container">
      <div class='item'>Item 1</div>
      <div class='item'>Item 2</div>
      <div class='item'>Item 3</div>
      <div class='item'>Item 4</div>
    </div>
  </body>
</html>

.item-container {
  display: flex;
}

div.item {
  background: #283747;
  color: white;
  margin: 1rem;
  flex: 1;
}

.flip {
  flex-direction: column; 
}
function toggle() {
  const itemContainer = document.querySelector('.item-container');
  itemContainer.classList.toggle('flip');
}

External CSS

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External JavaScript

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